You can do
orig.update(extra)
or, if you don’t want orig
to be modified, make a copy first:
dest = dict(orig) # or orig.copy()
dest.update(extra)
Note that if extra and orig have overlapping keys, the final value will be taken from extra. For example,
>>> d1 = {1: 1, 2: 2}
>>> d2 = {2: 'ha!', 3: 3}
>>> d1.update(d2)
>>> d1
{1: 1, 2: 'ha!', 3: 3}